Sampling devices of this type are known, for example, from Belgian Patent No. 871,391 or German Offenlegungschrift 35 40 228. These sampling devices can be part of a measuring head, with which measurements in molten metal can then be carried out or a sample withdrawn from the molten metal. The sampling device consists of two identical halves or half cups that enclose a hollow space or chamber. The two components of the sampling device are held together with a spring clip. An inlet pipe for the fluid metal opens into the chamber at its front end.
The measuring head with the sampling device is located on the end of a measuring lance. After the measuring lance is withdrawn from the molten metal to be analyzed, the sampling device can be removed from the measuring head. The solidified sample of molten metal is then located in the sampling device. The sample can ultimately be taken out by breaking open the sampling device in the area of the two cup-shaped metallic components that surround the chamber. The conventional chambers are formed in a way that yield flat, disk-shaped metallic samples. In some cases, the chamber of the sampling device can be subdivided into two chambers, whereby the chamber farther away from the inlet pipe usually has a substantially smaller thickness than the closer lying chamber. A sample is thereby produced with a thicker area and a thinner area, both of which can be drawn on in analyzing the metal.
The metallic components are galvanized with zinc so that they will not corrode while in storage.
It appears that breaking open the two cup-shaped, metallic components is problematical, since the fluid metal adheres to the components when it solidifies. This adherence can be so strong that the components must be mechanically removed, which can be very expensive. Even when the components are separable from one another by great force it has been observed that portions of the components still adhere to the metallic sample, thereby contaminating it. Since the components are galvanized with zinc, the sample is contaminated by this zinc or tends to form pores, so that the subsequent analysis of the sample yields an adulterated result. In addition, the mechanical force on the sample when the components are broken open can influence the structure of the metallic sample, if the components adhere to the sample, and the metallic sample can bend so that there is no longer a level work surface on the sample for subsequently removing any portion of the sample.